P. 148 of Theorem List - Intuitionistic Logic Explorer

Theorem List for Intuitionistic Logic Explorer - 14701-14800   *Has distinct variable group(s)

Type	Label	Description
Statement
Theorem	lspsncl 14701	The span of a singleton is a subspace (frequently used special case of lspcl 14700). (Contributed by NM, 17-Jul-2014.)
|- V = ( Base ` W )   &    |- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ X e. V ) -> ( N ` { X } ) e. S )
Theorem	lspprcl 14702	The span of a pair is a subspace (frequently used special case of lspcl 14700). (Contributed by NM, 11-Apr-2015.)
|- V = ( Base ` W )   &    |- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   =>    |- ( ph -> ( N ` { X , Y } ) e. S )
Theorem	lsptpcl 14703	The span of an unordered triple is a subspace (frequently used special case of lspcl 14700). (Contributed by NM, 22-May-2015.)
|- V = ( Base ` W )   &    |- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   &    |- ( ph -> Z e. V )   =>    |- ( ph -> ( N ` { X , Y , Z } ) e. S )
Theorem	lspex 14704	Existence of the span of a set of vectors. (Contributed by Jim Kingdon, 25-Apr-2025.)
|- ( W e. X -> ( LSpan ` W ) e. _V )
Theorem	lspsnsubg 14705	The span of a singleton is an additive subgroup (frequently used special case of lspcl 14700). (Contributed by Mario Carneiro, 21-Apr-2016.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ X e. V ) -> ( N ` { X } ) e. (SubGrp ` W ) )
Theorem	lspid 14706	The span of a subspace is itself. (Contributed by NM, 15-Dec-2013.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ U e. S ) -> ( N ` U ) = U )
Theorem	lspssv 14707	A span is a set of vectors. (Contributed by NM, 22-Feb-2014.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ U C_ V ) -> ( N ` U ) C_ V )
Theorem	lspss 14708	Span preserves subset ordering. (Contributed by NM, 11-Dec-2013.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ U C_ V /\ T C_ U ) -> ( N ` T ) C_ ( N ` U ) )
Theorem	lspssid 14709	A set of vectors is a subset of its span. (Contributed by NM, 6-Feb-2014.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ U C_ V ) -> U C_ ( N ` U ) )
Theorem	lspidm 14710	The span of a set of vectors is idempotent. (Contributed by NM, 22-Feb-2014.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ U C_ V ) -> ( N ` ( N ` U ) ) = ( N ` U ) )
Theorem	lspun 14711	The span of union is the span of the union of spans. (Contributed by NM, 22-Feb-2014.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ T C_ V /\ U C_ V ) -> ( N ` ( T u. U ) ) = ( N ` ( ( N ` T ) u. ( N ` U ) ) ) )
Theorem	lspssp 14712	If a set of vectors is a subset of a subspace, then the span of those vectors is also contained in the subspace. (Contributed by Mario Carneiro, 4-Sep-2014.)
|- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ U e. S /\ T C_ U ) -> ( N ` T ) C_ U )
Theorem	lspsnss 14713	The span of the singleton of a subspace member is included in the subspace. (Contributed by NM, 9-Apr-2014.) (Revised by Mario Carneiro, 4-Sep-2014.)
|- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ U e. S /\ X e. U ) -> ( N ` { X } ) C_ U )
Theorem	lspsnel3 14714	A member of the span of the singleton of a vector is a member of a subspace containing the vector. (Contributed by NM, 4-Jul-2014.)
|- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> U e. S )   &    |- ( ph -> X e. U )   &    |- ( ph -> Y e. ( N ` { X } ) )   =>    |- ( ph -> Y e. U )
Theorem	lspprss 14715	The span of a pair of vectors in a subspace belongs to the subspace. (Contributed by NM, 12-Jan-2015.)
|- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> U e. S )   &    |- ( ph -> X e. U )   &    |- ( ph -> Y e. U )   =>    |- ( ph -> ( N ` { X , Y } ) C_ U )
Theorem	lspsnid 14716	A vector belongs to the span of its singleton. (Contributed by NM, 9-Apr-2014.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ X e. V ) -> X e. ( N ` { X } ) )
Theorem	lspsnel6 14717	Relationship between a vector and the 1-dim (or 0-dim) subspace it generates. (Contributed by NM, 8-Aug-2014.) (Revised by Mario Carneiro, 8-Jan-2015.)
|- V = ( Base ` W )   &    |- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> U e. S )   =>    |- ( ph -> ( X e. U <-> ( X e. V /\ ( N ` { X } ) C_ U ) ) )
Theorem	lspsnel5 14718	Relationship between a vector and the 1-dim (or 0-dim) subspace it generates. (Contributed by NM, 8-Aug-2014.)
|- V = ( Base ` W )   &    |- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> U e. S )   &    |- ( ph -> X e. V )   =>    |- ( ph -> ( X e. U <-> ( N ` { X } ) C_ U ) )
Theorem	lspsnel5a 14719	Relationship between a vector and the 1-dim (or 0-dim) subspace it generates. (Contributed by NM, 20-Feb-2015.)
|- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> U e. S )   &    |- ( ph -> X e. U )   =>    |- ( ph -> ( N ` { X } ) C_ U )
Theorem	lspprid1 14720	A member of a pair of vectors belongs to their span. (Contributed by NM, 14-May-2015.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   =>    |- ( ph -> X e. ( N ` { X , Y } ) )
Theorem	lspprid2 14721	A member of a pair of vectors belongs to their span. (Contributed by NM, 14-May-2015.)
|- V = ( Base ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   =>    |- ( ph -> Y e. ( N ` { X , Y } ) )
Theorem	lspprvacl 14722	The sum of two vectors belongs to their span. (Contributed by NM, 20-May-2015.)
|- V = ( Base ` W )   &    |- .+ = ( +g ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   =>    |- ( ph -> ( X .+ Y ) e. ( N ` { X , Y } ) )
Theorem	lssats2 14723*	A way to express atomisticity (a subspace is the union of its atoms). (Contributed by NM, 3-Feb-2015.)
|- S = ( LSubSp ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> U e. S )   =>    |- ( ph -> U = U_ x e. U ( N ` { x } ) )
Theorem	lspsneli 14724	A scalar product with a vector belongs to the span of its singleton. (Contributed by NM, 2-Jul-2014.)
|- V = ( Base ` W )   &    |- .x. = ( .s ` W )   &    |- F = (Scalar ` W )   &    |- K = ( Base ` F )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> A e. K )   &    |- ( ph -> X e. V )   =>    |- ( ph -> ( A .x. X ) e. ( N ` { X } ) )
Theorem	lspsn 14725*	Span of the singleton of a vector. (Contributed by NM, 14-Jan-2014.) (Proof shortened by Mario Carneiro, 19-Jun-2014.)
|- F = (Scalar ` W )   &    |- K = ( Base ` F )   &    |- V = ( Base ` W )   &    |- .x. = ( .s ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ X e. V ) -> ( N ` { X } ) = { v | E. k e. K v = ( k .x. X ) } )
Theorem	ellspsn 14726*	Member of span of the singleton of a vector. (Contributed by NM, 22-Feb-2014.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- F = (Scalar ` W )   &    |- K = ( Base ` F )   &    |- V = ( Base ` W )   &    |- .x. = ( .s ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ X e. V ) -> ( U e. ( N ` { X } ) <-> E. k e. K U = ( k .x. X ) ) )
Theorem	lspsnvsi 14727	Span of a scalar product of a singleton. (Contributed by NM, 23-Apr-2014.) (Proof shortened by Mario Carneiro, 4-Sep-2014.)
|- F = (Scalar ` W )   &    |- K = ( Base ` F )   &    |- V = ( Base ` W )   &    |- .x. = ( .s ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ R e. K /\ X e. V ) -> ( N ` { ( R .x. X ) } ) C_ ( N ` { X } ) )
Theorem	lspsnss2 14728*	Comparable spans of singletons must have proportional vectors. (Contributed by NM, 7-Jun-2015.)
|- V = ( Base ` W )   &    |- S = (Scalar ` W )   &    |- K = ( Base ` S )   &    |- .x. = ( .s ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   =>    |- ( ph -> ( ( N ` { X } ) C_ ( N ` { Y } ) <-> E. k e. K X = ( k .x. Y ) ) )
Theorem	lspsnneg 14729	Negation does not change the span of a singleton. (Contributed by NM, 24-Apr-2014.) (Proof shortened by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- M = ( invg ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ X e. V ) -> ( N ` { ( M ` X ) } ) = ( N ` { X } ) )
Theorem	lspsnsub 14730	Swapping subtraction order does not change the span of a singleton. (Contributed by NM, 4-Apr-2015.)
|- V = ( Base ` W )   &    |- .- = ( -g ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   =>    |- ( ph -> ( N ` { ( X .- Y ) } ) = ( N ` { ( Y .- X ) } ) )
Theorem	lspsn0 14731	Span of the singleton of the zero vector. (Contributed by NM, 15-Jan-2014.) (Proof shortened by Mario Carneiro, 19-Jun-2014.)
|- .0. = ( 0g ` W )   &    |- N = ( LSpan ` W )   =>    |- ( W e. LMod -> ( N ` { .0. } ) = { .0. } )
Theorem	lsp0 14732	Span of the empty set. (Contributed by Mario Carneiro, 5-Sep-2014.)
|- .0. = ( 0g ` W )   &    |- N = ( LSpan ` W )   =>    |- ( W e. LMod -> ( N ` (/) ) = { .0. } )
Theorem	lspuni0 14733	Union of the span of the empty set. (Contributed by NM, 14-Mar-2015.)
|- .0. = ( 0g ` W )   &    |- N = ( LSpan ` W )   =>    |- ( W e. LMod -> U. ( N ` (/) ) = .0. )
Theorem	lspun0 14734	The span of a union with the zero subspace. (Contributed by NM, 22-May-2015.)
|- V = ( Base ` W )   &    |- .0. = ( 0g ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X C_ V )   =>    |- ( ph -> ( N ` ( X u. { .0. } ) ) = ( N ` X ) )
Theorem	lspsneq0 14735	Span of the singleton is the zero subspace iff the vector is zero. (Contributed by NM, 27-Apr-2014.) (Revised by Mario Carneiro, 19-Jun-2014.)
|- V = ( Base ` W )   &    |- .0. = ( 0g ` W )   &    |- N = ( LSpan ` W )   =>    |- ( ( W e. LMod /\ X e. V ) -> ( ( N ` { X } ) = { .0. } <-> X = .0. ) )
Theorem	lspsneq0b 14736	Equal singleton spans imply both arguments are zero or both are nonzero. (Contributed by NM, 21-Mar-2015.)
|- V = ( Base ` W )   &    |- .0. = ( 0g ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   &    |- ( ph -> ( N ` { X } ) = ( N ` { Y } ) )   =>    |- ( ph -> ( X = .0. <-> Y = .0. ) )
Theorem	lmodindp1 14737	Two independent (non-colinear) vectors have nonzero sum. (Contributed by NM, 22-Apr-2015.)
|- V = ( Base ` W )   &    |- .+ = ( +g ` W )   &    |- .0. = ( 0g ` W )   &    |- N = ( LSpan ` W )   &    |- ( ph -> W e. LMod )   &    |- ( ph -> X e. V )   &    |- ( ph -> Y e. V )   &    |- ( ph -> ( N ` { X } ) =/= ( N ` { Y } ) )   =>    |- ( ph -> ( X .+ Y ) =/= .0. )
Theorem	lsslsp 14738	Spans in submodules correspond to spans in the containing module. (Contributed by Stefan O'Rear, 12-Dec-2014.) Terms in the equation were swapped as proposed by NM on 15-Mar-2015. (Revised by AV, 18-Apr-2025.)
|- X = ( W ↾s U )   &    |- M = ( LSpan ` W )   &    |- N = ( LSpan ` X )   &    |- L = ( LSubSp ` W )   =>    |- ( ( W e. LMod /\ U e. L /\ G C_ U ) -> ( N ` G ) = ( M ` G ) )
Theorem	lss0v 14739	The zero vector in a submodule equals the zero vector in the including module. (Contributed by NM, 15-Mar-2015.)
|- X = ( W ↾s U )   &    |- .0. = ( 0g ` W )   &    |- Z = ( 0g ` X )   &    |- L = ( LSubSp ` W )   =>    |- ( ( W e. LMod /\ U e. L ) -> Z = .0. )
Theorem	lsspropdg 14740*	If two structures have the same components (properties), they have the same subspace structure. (Contributed by Mario Carneiro, 9-Feb-2015.) (Revised by Mario Carneiro, 14-Jun-2015.)
|- ( ph -> B = ( Base ` K ) )   &    |- ( ph -> B = ( Base ` L ) )   &    |- ( ph -> B C_ W )   &    |- ( ( ph /\ ( x e. W /\ y e. W ) ) -> ( x ( +g ` K ) y ) = ( x ( +g ` L ) y ) )   &    |- ( ( ph /\ ( x e. P /\ y e. B ) ) -> ( x ( .s ` K ) y ) e. W )   &    |- ( ( ph /\ ( x e. P /\ y e. B ) ) -> ( x ( .s ` K ) y ) = ( x ( .s ` L ) y ) )   &    |- ( ph -> P = ( Base ` (Scalar ` K ) ) )   &    |- ( ph -> P = ( Base ` (Scalar ` L ) ) )   &    |- ( ph -> K e. X )   &    |- ( ph -> L e. Y )   =>    |- ( ph -> ( LSubSp ` K ) = ( LSubSp ` L ) )
Theorem	lsppropd 14741*	If two structures have the same components (properties), they have the same span function. (Contributed by Mario Carneiro, 9-Feb-2015.) (Revised by Mario Carneiro, 14-Jun-2015.) (Revised by AV, 24-Apr-2024.)
|- ( ph -> B = ( Base ` K ) )   &    |- ( ph -> B = ( Base ` L ) )   &    |- ( ph -> B C_ W )   &    |- ( ( ph /\ ( x e. W /\ y e. W ) ) -> ( x ( +g ` K ) y ) = ( x ( +g ` L ) y ) )   &    |- ( ( ph /\ ( x e. P /\ y e. B ) ) -> ( x ( .s ` K ) y ) e. W )   &    |- ( ( ph /\ ( x e. P /\ y e. B ) ) -> ( x ( .s ` K ) y ) = ( x ( .s ` L ) y ) )   &    |- ( ph -> P = ( Base ` (Scalar ` K ) ) )   &    |- ( ph -> P = ( Base ` (Scalar ` L ) ) )   &    |- ( ph -> K e. X )   &    |- ( ph -> L e. Y )   =>    |- ( ph -> ( LSpan ` K ) = ( LSpan ` L ) )
7.6  Subring algebras and ideals
7.6.1  Subring algebras
Syntax	csra 14742	Extend class notation with the subring algebra generator.
class subringAlg
Syntax	crglmod 14743	Extend class notation with the left module induced by a ring over itself.
class ringLMod
Definition	df-sra 14744*	Any ring can be regarded as a left algebra over any of its subrings. The function subringAlg associates with any ring and any of its subrings the left algebra consisting in the ring itself regarded as a left algebra over the subring. It has an inner product which is simply the ring product. (Contributed by Mario Carneiro, 27-Nov-2014.) (Revised by Thierry Arnoux, 16-Jun-2019.)
|- subringAlg = ( w e. _V |-> ( s e. ~P ( Base ` w ) |-> ( ( ( w sSet <. (Scalar ` ndx ) , ( w ↾s s ) >. ) sSet <. ( .s ` ndx ) , ( .r ` w ) >. ) sSet <. ( .i ` ndx ) , ( .r ` w ) >. ) ) )
Definition	df-rgmod 14745	Any ring can be regarded as a left algebra over itself. The function ringLMod associates with any ring the left algebra consisting in the ring itself regarded as a left algebra over itself. It has an inner product which is simply the ring product. (Contributed by Stefan O'Rear, 6-Dec-2014.)
|- ringLMod = ( w e. _V |-> ( (subringAlg ` w ) ` ( Base ` w ) ) )
Theorem	sraval 14746	Lemma for srabaseg 14748 through sravscag 14752. (Contributed by Mario Carneiro, 27-Nov-2014.) (Revised by Thierry Arnoux, 16-Jun-2019.)
|- ( ( W e. V /\ S C_ ( Base ` W ) ) -> ( (subringAlg ` W ) ` S ) = ( ( ( W sSet <. (Scalar ` ndx ) , ( W ↾s S ) >. ) sSet <. ( .s ` ndx ) , ( .r ` W ) >. ) sSet <. ( .i ` ndx ) , ( .r ` W ) >. ) )
Theorem	sralemg 14747	Lemma for srabaseg 14748 and similar theorems. (Contributed by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Revised by AV, 29-Oct-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   &    |- ( E = Slot ( E ` ndx ) /\ ( E ` ndx ) e. NN )   &    |- (Scalar ` ndx ) =/= ( E ` ndx )   &    |- ( .s ` ndx ) =/= ( E ` ndx )   &    |- ( .i ` ndx ) =/= ( E ` ndx )   =>    |- ( ph -> ( E ` W ) = ( E ` A ) )
Theorem	srabaseg 14748	Base set of a subring algebra. (Contributed by Stefan O'Rear, 27-Nov-2014.) (Revised by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Revised by AV, 29-Oct-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( Base ` W ) = ( Base ` A ) )
Theorem	sraaddgg 14749	Additive operation of a subring algebra. (Contributed by Stefan O'Rear, 27-Nov-2014.) (Revised by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Revised by AV, 29-Oct-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( +g ` W ) = ( +g ` A ) )
Theorem	sramulrg 14750	Multiplicative operation of a subring algebra. (Contributed by Stefan O'Rear, 27-Nov-2014.) (Revised by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Revised by AV, 29-Oct-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( .r ` W ) = ( .r ` A ) )
Theorem	srascag 14751	The set of scalars of a subring algebra. (Contributed by Stefan O'Rear, 27-Nov-2014.) (Revised by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Proof shortened by AV, 12-Nov-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( W ↾s S ) = (Scalar ` A ) )
Theorem	sravscag 14752	The scalar product operation of a subring algebra. (Contributed by Stefan O'Rear, 27-Nov-2014.) (Revised by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Proof shortened by AV, 12-Nov-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( .r ` W ) = ( .s ` A ) )
Theorem	sraipg 14753	The inner product operation of a subring algebra. (Contributed by Thierry Arnoux, 16-Jun-2019.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( .r ` W ) = ( .i ` A ) )
Theorem	sratsetg 14754	Topology component of a subring algebra. (Contributed by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Revised by AV, 29-Oct-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> (TopSet ` W ) = (TopSet ` A ) )
Theorem	sraex 14755	Existence of a subring algebra. (Contributed by Jim Kingdon, 16-Apr-2025.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> A e. _V )
Theorem	sratopng 14756	Topology component of a subring algebra. (Contributed by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( TopOpen ` W ) = ( TopOpen ` A ) )
Theorem	sradsg 14757	Distance function of a subring algebra. (Contributed by Mario Carneiro, 4-Oct-2015.) (Revised by Thierry Arnoux, 16-Jun-2019.) (Revised by AV, 29-Oct-2024.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> ( dist ` W ) = ( dist ` A ) )
Theorem	sraring 14758	Condition for a subring algebra to be a ring. (Contributed by Thierry Arnoux, 24-Jul-2023.)
|- A = ( (subringAlg ` R ) ` V )   &    |- B = ( Base ` R )   =>    |- ( ( R e. Ring /\ V C_ B ) -> A e. Ring )
Theorem	sralmod 14759	The subring algebra is a left module. (Contributed by Stefan O'Rear, 27-Nov-2014.)
|- A = ( (subringAlg ` W ) ` S )   =>    |- ( S e. (SubRing ` W ) -> A e. LMod )
Theorem	sralmod0g 14760	The subring module inherits a zero from its ring. (Contributed by Stefan O'Rear, 27-Dec-2014.)
|- ( ph -> A = ( (subringAlg ` W ) ` S ) )   &    |- ( ph -> .0. = ( 0g ` W ) )   &    |- ( ph -> S C_ ( Base ` W ) )   &    |- ( ph -> W e. X )   =>    |- ( ph -> .0. = ( 0g ` A ) )
Theorem	issubrgd 14761*	Prove a subring by closure (definition version). (Contributed by Stefan O'Rear, 7-Dec-2014.)
|- ( ph -> S = ( I ↾s D ) )   &    |- ( ph -> .0. = ( 0g ` I ) )   &    |- ( ph -> .+ = ( +g ` I ) )   &    |- ( ph -> D C_ ( Base ` I ) )   &    |- ( ph -> .0. e. D )   &    |- ( ( ph /\ x e. D /\ y e. D ) -> ( x .+ y ) e. D )   &    |- ( ( ph /\ x e. D ) -> ( ( invg ` I ) ` x ) e. D )   &    |- ( ph -> .1. = ( 1r ` I ) )   &    |- ( ph -> .x. = ( .r ` I ) )   &    |- ( ph -> .1. e. D )   &    |- ( ( ph /\ x e. D /\ y e. D ) -> ( x .x. y ) e. D )   &    |- ( ph -> I e. Ring )   =>    |- ( ph -> D e. (SubRing ` I ) )
Theorem	rlmfn 14762	ringLMod is a function. (Contributed by Stefan O'Rear, 6-Dec-2014.)
|- ringLMod Fn _V
Theorem	rlmvalg 14763	Value of the ring module. (Contributed by Stefan O'Rear, 31-Mar-2015.)
|- ( W e. V -> (ringLMod ` W ) = ( (subringAlg ` W ) ` ( Base ` W ) ) )
Theorem	rlmbasg 14764	Base set of the ring module. (Contributed by Stefan O'Rear, 31-Mar-2015.)
|- ( R e. V -> ( Base ` R ) = ( Base ` (ringLMod ` R ) ) )
Theorem	rlmplusgg 14765	Vector addition in the ring module. (Contributed by Stefan O'Rear, 31-Mar-2015.)
|- ( R e. V -> ( +g ` R ) = ( +g ` (ringLMod ` R ) ) )
Theorem	rlm0g 14766	Zero vector in the ring module. (Contributed by Stefan O'Rear, 6-Dec-2014.) (Revised by Mario Carneiro, 2-Oct-2015.)
|- ( R e. V -> ( 0g ` R ) = ( 0g ` (ringLMod ` R ) ) )
Theorem	rlmsubg 14767	Subtraction in the ring module. (Contributed by Thierry Arnoux, 30-Jun-2019.)
|- ( R e. V -> ( -g ` R ) = ( -g ` (ringLMod ` R ) ) )
Theorem	rlmmulrg 14768	Ring multiplication in the ring module. (Contributed by Mario Carneiro, 6-Oct-2015.)
|- ( R e. V -> ( .r ` R ) = ( .r ` (ringLMod ` R ) ) )
Theorem	rlmscabas 14769	Scalars in the ring module have the same base set. (Contributed by Jim Kingdon, 29-Apr-2025.)
|- ( R e. X -> ( Base ` R ) = ( Base ` (Scalar ` (ringLMod ` R ) ) ) )
Theorem	rlmvscag 14770	Scalar multiplication in the ring module. (Contributed by Stefan O'Rear, 31-Mar-2015.)
|- ( R e. V -> ( .r ` R ) = ( .s ` (ringLMod ` R ) ) )
Theorem	rlmtopng 14771	Topology component of the ring module. (Contributed by Mario Carneiro, 6-Oct-2015.)
|- ( R e. V -> ( TopOpen ` R ) = ( TopOpen ` (ringLMod ` R ) ) )
Theorem	rlmdsg 14772	Metric component of the ring module. (Contributed by Mario Carneiro, 6-Oct-2015.)
|- ( R e. V -> ( dist ` R ) = ( dist ` (ringLMod ` R ) ) )
Theorem	rlmlmod 14773	The ring module is a module. (Contributed by Stefan O'Rear, 6-Dec-2014.)
|- ( R e. Ring -> (ringLMod ` R ) e. LMod )
Theorem	rlmvnegg 14774	Vector negation in the ring module. (Contributed by Stefan O'Rear, 6-Dec-2014.) (Revised by Mario Carneiro, 5-Jun-2015.)
|- ( R e. V -> ( invg ` R ) = ( invg ` (ringLMod ` R ) ) )
Theorem	ixpsnbasval 14775*	The value of an infinite Cartesian product of the base of a left module over a ring with a singleton. (Contributed by AV, 3-Dec-2018.)
|- ( ( R e. V /\ X e. W ) -> X_ x e. { X } ( Base ` ( ( { X } X. { (ringLMod ` R ) } ) ` x ) ) = { f | ( f Fn { X } /\ ( f ` X ) e. ( Base ` R ) ) } )
7.6.2  Ideals and spans
Syntax	clidl 14776	Ring left-ideal function.
class LIdeal
Syntax	crsp 14777	Ring span function.
class RSpan
Definition	df-lidl 14778	Define the class of left ideals of a given ring. An ideal is a submodule of the ring viewed as a module over itself. (Contributed by Stefan O'Rear, 31-Mar-2015.)
|- LIdeal = ( LSubSp o. ringLMod )
Definition	df-rsp 14779	Define the linear span function in a ring (Ideal generator). (Contributed by Stefan O'Rear, 4-Apr-2015.)
|- RSpan = ( LSpan o. ringLMod )
Theorem	lidlvalg 14780	Value of the set of ring ideals. (Contributed by Stefan O'Rear, 31-Mar-2015.)
|- ( W e. V -> (LIdeal ` W ) = ( LSubSp ` (ringLMod ` W ) ) )
Theorem	rspvalg 14781	Value of the ring span function. (Contributed by Stefan O'Rear, 4-Apr-2015.)
|- ( W e. V -> (RSpan ` W ) = ( LSpan ` (ringLMod ` W ) ) )
Theorem	lidlex 14782	Existence of the set of left ideals. (Contributed by Jim Kingdon, 27-Apr-2025.)
|- ( W e. V -> (LIdeal ` W ) e. _V )
Theorem	rspex 14783	Existence of the ring span. (Contributed by Jim Kingdon, 25-Apr-2025.)
|- ( W e. V -> (RSpan ` W ) e. _V )
Theorem	lidlmex 14784	Existence of the set a left ideal is built from (when the ideal is inhabited). (Contributed by Jim Kingdon, 18-Apr-2025.)
|- I = (LIdeal ` W )   =>    |- ( U e. I -> W e. _V )
Theorem	lidlss 14785	An ideal is a subset of the base set. (Contributed by Stefan O'Rear, 28-Mar-2015.)
|- B = ( Base ` W )   &    |- I = (LIdeal ` W )   =>    |- ( U e. I -> U C_ B )
Theorem	lidlssbas 14786	The base set of the restriction of the ring to a (left) ideal is a subset of the base set of the ring. (Contributed by AV, 17-Feb-2020.)
|- L = (LIdeal ` R )   &    |- I = ( R ↾s U )   =>    |- ( U e. L -> ( Base ` I ) C_ ( Base ` R ) )
Theorem	lidlbas 14787	A (left) ideal of a ring is the base set of the restriction of the ring to this ideal. (Contributed by AV, 17-Feb-2020.)
|- L = (LIdeal ` R )   &    |- I = ( R ↾s U )   =>    |- ( U e. L -> ( Base ` I ) = U )
Theorem	islidlm 14788*	Predicate of being a (left) ideal. (Contributed by Stefan O'Rear, 1-Apr-2015.)
|- U = (LIdeal ` R )   &    |- B = ( Base ` R )   &    |- .+ = ( +g ` R )   &    |- .x. = ( .r ` R )   =>    |- ( I e. U <-> ( I C_ B /\ E. j j e. I /\ A. x e. B A. a e. I A. b e. I ( ( x .x. a ) .+ b ) e. I ) )
Theorem	rnglidlmcl 14789	A (left) ideal containing the zero element is closed under left-multiplication by elements of the full non-unital ring. If the ring is not a unital ring, and the ideal does not contain the zero element of the ring, then the closure cannot be proven. (Contributed by AV, 18-Feb-2025.)
|- .0. = ( 0g ` R )   &    |- B = ( Base ` R )   &    |- .x. = ( .r ` R )   &    |- U = (LIdeal ` R )   =>    |- ( ( ( R e. Rng /\ I e. U /\ .0. e. I ) /\ ( X e. B /\ Y e. I ) ) -> ( X .x. Y ) e. I )
Theorem	dflidl2rng 14790*	Alternate (the usual textbook) definition of a (left) ideal of a non-unital ring to be a subgroup of the additive group of the ring which is closed under left-multiplication by elements of the full ring. (Contributed by AV, 21-Mar-2025.)
|- U = (LIdeal ` R )   &    |- B = ( Base ` R )   &    |- .x. = ( .r ` R )   =>    |- ( ( R e. Rng /\ I e. (SubGrp ` R ) ) -> ( I e. U <-> A. x e. B A. y e. I ( x .x. y ) e. I ) )
Theorem	isridlrng 14791*	A right ideal is a left ideal of the opposite non-unital ring. This theorem shows that this definition corresponds to the usual textbook definition of a right ideal of a ring to be a subgroup of the additive group of the ring which is closed under right-multiplication by elements of the full ring. (Contributed by AV, 21-Mar-2025.)
|- U = (LIdeal ` (oppr ` R ) )   &    |- B = ( Base ` R )   &    |- .x. = ( .r ` R )   =>    |- ( ( R e. Rng /\ I e. (SubGrp ` R ) ) -> ( I e. U <-> A. x e. B A. y e. I ( y .x. x ) e. I ) )
Theorem	lidl0cl 14792	An ideal contains 0. (Contributed by Stefan O'Rear, 3-Jan-2015.)
|- U = (LIdeal ` R )   &    |- .0. = ( 0g ` R )   =>    |- ( ( R e. Ring /\ I e. U ) -> .0. e. I )
Theorem	lidlacl 14793	An ideal is closed under addition. (Contributed by Stefan O'Rear, 3-Jan-2015.)
|- U = (LIdeal ` R )   &    |- .+ = ( +g ` R )   =>    |- ( ( ( R e. Ring /\ I e. U ) /\ ( X e. I /\ Y e. I ) ) -> ( X .+ Y ) e. I )
Theorem	lidlnegcl 14794	An ideal contains negatives. (Contributed by Stefan O'Rear, 3-Jan-2015.)
|- U = (LIdeal ` R )   &    |- N = ( invg ` R )   =>    |- ( ( R e. Ring /\ I e. U /\ X e. I ) -> ( N ` X ) e. I )
Theorem	lidlsubg 14795	An ideal is a subgroup of the additive group. (Contributed by Mario Carneiro, 14-Jun-2015.)
|- U = (LIdeal ` R )   =>    |- ( ( R e. Ring /\ I e. U ) -> I e. (SubGrp ` R ) )
Theorem	lidlsubcl 14796	An ideal is closed under subtraction. (Contributed by Stefan O'Rear, 28-Mar-2015.) (Proof shortened by OpenAI, 25-Mar-2020.)
|- U = (LIdeal ` R )   &    |- .- = ( -g ` R )   =>    |- ( ( ( R e. Ring /\ I e. U ) /\ ( X e. I /\ Y e. I ) ) -> ( X .- Y ) e. I )
Theorem	dflidl2 14797*	Alternate (the usual textbook) definition of a (left) ideal of a ring to be a subgroup of the additive group of the ring which is closed under left-multiplication by elements of the full ring. (Contributed by AV, 13-Feb-2025.) (Proof shortened by AV, 18-Apr-2025.)
|- U = (LIdeal ` R )   &    |- B = ( Base ` R )   &    |- .x. = ( .r ` R )   =>    |- ( R e. Ring -> ( I e. U <-> ( I e. (SubGrp ` R ) /\ A. x e. B A. y e. I ( x .x. y ) e. I ) ) )
Theorem	lidl0 14798	Every ring contains a zero ideal. (Contributed by Stefan O'Rear, 3-Jan-2015.)
|- U = (LIdeal ` R )   &    |- .0. = ( 0g ` R )   =>    |- ( R e. Ring -> { .0. } e. U )
Theorem	lidl1 14799	Every ring contains a unit ideal. (Contributed by Stefan O'Rear, 3-Jan-2015.)
|- U = (LIdeal ` R )   &    |- B = ( Base ` R )   =>    |- ( R e. Ring -> B e. U )
Theorem	rspcl 14800	The span of a set of ring elements is an ideal. (Contributed by Stefan O'Rear, 3-Jan-2015.) (Revised by Mario Carneiro, 2-Oct-2015.)
|- K = (RSpan ` R )   &    |- B = ( Base ` R )   &    |- U = (LIdeal ` R )   =>    |- ( ( R e. Ring /\ G C_ B ) -> ( K ` G ) e. U )